1 // Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef FORTRAN_EVALUATE_CHARACTER_H_ 16 #define FORTRAN_EVALUATE_CHARACTER_H_ 17 18 #include "type.h" 19 #include <string> 20 21 // Provides implementations of intrinsic functions operating on character 22 // scalars. No assumption is made regarding character encodings other than they 23 // must be compatible with ASCII (else, NEW_LINE, ACHAR and IACHAR need to be 24 // adapted). 25 26 namespace Fortran::evaluate { 27 28 template<int KIND> class CharacterUtils { 29 using Character = Scalar<Type<TypeCategory::Character, KIND>>; 30 using CharT = typename Character::value_type; 31 32 public: 33 // CHAR also implements ACHAR under assumption that character encodings 34 // contain ASCII CHAR(std::uint64_t code)35 static Character CHAR(std::uint64_t code) { 36 return Character{{static_cast<CharT>(code)}}; 37 } 38 39 // ICHAR also implements IACHAR under assumption that character encodings 40 // contain ASCII ICHAR(const Character & c)41 static std::int64_t ICHAR(const Character &c) { 42 CHECK(c.length() == 1); 43 if constexpr (std::is_same_v<CharT, char>) { 44 // char may be signed, so cast it first to unsigned to avoid having 45 // ichar(char(128_4)) returning -128 46 return static_cast<unsigned char>(c[0]); 47 } else { 48 return c[0]; 49 } 50 } 51 NEW_LINE()52 static Character NEW_LINE() { return Character{{NewLine()}}; } 53 ADJUSTL(const Character & str)54 static Character ADJUSTL(const Character &str) { 55 auto pos{str.find_first_not_of(Space())}; 56 if (pos != Character::npos && pos != 0) { 57 return Character{str.substr(pos) + Character(pos, Space())}; 58 } 59 // else empty or only spaces, or no leading spaces 60 return str; 61 } 62 ADJUSTR(const Character & str)63 static Character ADJUSTR(const Character &str) { 64 auto pos{str.find_last_not_of(Space())}; 65 if (pos != Character::npos && pos != str.length() - 1) { 66 auto delta{str.length() - 1 - pos}; 67 return Character{Character(delta, Space()) + str.substr(0, pos + 1)}; 68 } 69 // else empty or only spaces, or no trailing spaces 70 return str; 71 } 72 73 private: 74 // Following helpers assume that character encodings contain ASCII Space()75 static constexpr CharT Space() { return 0x20; } NewLine()76 static constexpr CharT NewLine() { return 0x0a; } 77 }; 78 79 } 80 81 #endif // FORTRAN_EVALUATE_CHARACTER_H_ 82